On 02/10/2021 01:05, Brian Gregory wrote:
> On 01/10/2021 08:40, SH wrote:
>> Halons are also known as CFC's Chloro - Fluoro carbons.
>>
>> They were heavily used in refrigeration, air conditioning, fire
>> suppression systems and as an aerosol can propellant.
>>
>> It used to even be used in Tippex and Snopake until the water based
>> versions versions came along.
>>
>> Now its R134a  which has now been replaced with R1234yf
>>
>> https://www.climalife.co.uk/r134a
>>
>>
>> https://www.climalife.co.uk/r1234yf
>
> Those pages discuss r134a and r1234yf being used for refrigeration.
> The penultimate paragraph on the latter page says "R1234yf has an ASHRAE
> class A2L which means it’s mildly flammable." so I doubt it's used for
> fire suppression.
>
> Anyone know what gets used for fire suppression nowadays?
>

I don't know how popular it is now (been 12 yrs), but there is a
replacement gas called Inergen,

http://www.tyco.no/products/Gaseous-Fire-Suppression/inergen-overview

which when deployed reduces oxygen content of the room mix and also
calms down humans so that they reduce anxiety breathing rate.

Inergen gas dump
https://www.youtube.com/watch?v=0F7qyY15_14

Nice demo. Participants so willing!

--
Adrian C

On 02/10/2021 08:13, Jeff Layman wrote:
>
> Here you go, JJ - become a Google expert like me!
> <https://surreyfire.co.uk/fire-extinguisher-colours/>
>
> Looks like it's dry powder or CO2 for electrical/computer fires if a
> hand extinguisher is used, but for what's used for whole room
> suppression see below. BTW, the link on the page above to "Wet chemical"
> ends at a 404. There is a working link from
> <https://surreyfire.co.uk/types-of-fire-extinguisher/> (which is similar
> to the first link with different emphases). I expected it to be an
> organic compound, but it appears to be a potassium salt water-based
> product.

Thanks, that's a good link. I didn't realise that even the actual
colour of the extinguishers had changed, and that the colours I remember
for the whole unit are now just bands across the top of the whole unit.

> One website for room fire suppression at
> <https://www.safelincs.co.uk/redetec-novec1230-automatic-fire-suppression-unit/?q=Novec+1230>
> turns up with "Novel 1230" as the fire suppressant. I had to go to the
> MSDS to see what that was, and it is listed as:
> 1, 1, 1, 2, 2, 4, 5, 5, 5 – Nonafluoro-4-(Trifluoromethyl)-3-Pentanone
> (misspelt in both the MSDS and Data Sheet in different ways!).
>
> There's another halocarbon mentioned elsewhere (HCFC-123, R-123 -
> 1,1-Dichloro-2,2,2,-Trifluoroethane), and I suspect there are others.

I presume that these are variants that don't harm the ozone layer that
have been developed since. I remember my then boss being concerned at
the time about the implications for his business.

--

Fake news kills!

I may be contacted via the contact address given on my website:
www.macfh.co.uk

Adrian Caspersz <email@here.invalid> wrote:
> On 02/10/2021 01:05, Brian Gregory wrote:
>> On 01/10/2021 08:40, SH wrote:
>>> Halons are also known as CFC's Chloro - Fluoro carbons.
>>>
>>> They were heavily used in refrigeration, air conditioning, fire
>>> suppression systems and as an aerosol can propellant.
>>>
>>> It used to even be used in Tippex and Snopake until the water based
>>> versions versions came along.
>>>
>>> Now its R134a  which has now been replaced with R1234yf
>>>
>>> https://www.climalife.co.uk/r134a
>>>
>>>
>>> https://www.climalife.co.uk/r1234yf
>>
>> Those pages discuss r134a and r1234yf being used for refrigeration.
>> The penultimate paragraph on the latter page says "R1234yf has an ASHRAE
>> class A2L which means it’s mildly flammable." so I doubt it's used for
>> fire suppression.
>>
>> Anyone know what gets used for fire suppression nowadays?
>>
>
> I don't know how popular it is now (been 12 yrs), but there is a
> replacement gas called Inergen,
>
> http://www.tyco.no/products/Gaseous-Fire-Suppression/inergen-overview
>
> which when deployed reduces oxygen content of the room mix and also
> calms down humans so that they reduce anxiety breathing rate.
>
> Inergen gas dump
> https://www.youtube.com/watch?v=0F7qyY15_14
>
> Nice demo. Participants so willing!
>

Genuine question - why can’t you use nitrogen to suppress fire in a data
centre?

On 02/10/2021 11:45, Tweed wrote:
> Adrian Caspersz <email@here.invalid> wrote:
>> On 02/10/2021 01:05, Brian Gregory wrote:
>>> On 01/10/2021 08:40, SH wrote:
>>>> Halons are also known as CFC's Chloro - Fluoro carbons.
>>>>
>>>> They were heavily used in refrigeration, air conditioning, fire
>>>> suppression systems and as an aerosol can propellant.
>>>>
>>>> It used to even be used in Tippex and Snopake until the water based
>>>> versions versions came along.
>>>>
>>>> Now its R134a  which has now been replaced with R1234yf
>>>>
>>>> https://www.climalife.co.uk/r134a
>>>>
>>>>
>>>> https://www.climalife.co.uk/r1234yf
>>>
>>> Those pages discuss r134a and r1234yf being used for refrigeration.
>>> The penultimate paragraph on the latter page says "R1234yf has an ASHRAE
>>> class A2L which means it’s mildly flammable." so I doubt it's used for
>>> fire suppression.
>>>
>>> Anyone know what gets used for fire suppression nowadays?
>>>
>>
>> I don't know how popular it is now (been 12 yrs), but there is a
>> replacement gas called Inergen,
>>
>> http://www.tyco.no/products/Gaseous-Fire-Suppression/inergen-overview
>>
>> which when deployed reduces oxygen content of the room mix and also
>> calms down humans so that they reduce anxiety breathing rate.
>>
>> Inergen gas dump
>> https://www.youtube.com/watch?v=0F7qyY15_14
>>
>> Nice demo. Participants so willing!
>>
>
> Genuine question - why can’t you use nitrogen to suppress fire in a data
> centre?
>

The atmosphere comprises of 78% nitrogen already. The level of Oxygen is
about 21% with about 1% Argon.

Remember the triangle of fire.... Oxygen - heat - fuel.

You need to remove of these to extinguish the fire effectively.

It is the 78% nitrogen in the atmosphere that leads to the formation of
nitrogen oxides from vehicle engines, the NOX would fall if we supplied
pure oxygen from cylinders rather than the ambient atmosphere

So in a fire, you'd be making NOx due to the atmosphere containing both
nitrogen and oxygen,

So you need a way of scavenging the oxygen quickly to quench a fire.
Thats why Halons were preferred as they do react with both oxygen and ozone.

Another method is to use a gas or solid that decomposes when in contact
with a flame to retard the fire. This is the prupose of antimony
trioxide when added to flammable plastics to impart fire retardancy.

S.

SH <i.love.spam@spam.com> wrote:
> On 02/10/2021 11:45, Tweed wrote:
>> Adrian Caspersz <email@here.invalid> wrote:
>>> On 02/10/2021 01:05, Brian Gregory wrote:
>>>> On 01/10/2021 08:40, SH wrote:
>>>>> Halons are also known as CFC's Chloro - Fluoro carbons.
>>>>>
>>>>> They were heavily used in refrigeration, air conditioning, fire
>>>>> suppression systems and as an aerosol can propellant.
>>>>>
>>>>> It used to even be used in Tippex and Snopake until the water based
>>>>> versions versions came along.
>>>>>
>>>>> Now its R134a  which has now been replaced with R1234yf
>>>>>
>>>>> https://www.climalife.co.uk/r134a
>>>>>
>>>>>
>>>>> https://www.climalife.co.uk/r1234yf
>>>>
>>>> Those pages discuss r134a and r1234yf being used for refrigeration.
>>>> The penultimate paragraph on the latter page says "R1234yf has an ASHRAE
>>>> class A2L which means it’s mildly flammable." so I doubt it's used for
>>>> fire suppression.
>>>>
>>>> Anyone know what gets used for fire suppression nowadays?
>>>>
>>>
>>> I don't know how popular it is now (been 12 yrs), but there is a
>>> replacement gas called Inergen,
>>>
>>> http://www.tyco.no/products/Gaseous-Fire-Suppression/inergen-overview
>>>
>>> which when deployed reduces oxygen content of the room mix and also
>>> calms down humans so that they reduce anxiety breathing rate.
>>>
>>> Inergen gas dump
>>> https://www.youtube.com/watch?v=0F7qyY15_14
>>>
>>> Nice demo. Participants so willing!
>>>
>>
>> Genuine question - why can’t you use nitrogen to suppress fire in a data
>> centre?
>>
>
> The atmosphere comprises of 78% nitrogen already. The level of Oxygen is
> about 21% with about 1% Argon.
>
> Remember the triangle of fire.... Oxygen - heat - fuel.
>
> You need to remove of these to extinguish the fire effectively.
>
> It is the 78% nitrogen in the atmosphere that leads to the formation of
> nitrogen oxides from vehicle engines, the NOX would fall if we supplied
> pure oxygen from cylinders rather than the ambient atmosphere
>
> So in a fire, you'd be making NOx due to the atmosphere containing both
> nitrogen and oxygen,
>
> So you need a way of scavenging the oxygen quickly to quench a fire.
> Thats why Halons were preferred as they do react with both oxygen and ozone.
>
> Another method is to use a gas or solid that decomposes when in contact
> with a flame to retard the fire. This is the prupose of antimony
> trioxide when added to flammable plastics to impart fire retardancy.
>
> S.
>
>
Thank you, but I’m not sure I fully understand. If you vent a large volume
of nitrogen into the room isn’t it going to displace the oxygen?

On Sat, 02 Oct 2021 08:44:29 +0100, charles <charles@candehope.me.uk> wrote:

>In article <sj89rf$hkk$1@gioia.aioe.org>,
> Java Jive <java@evij.com.invalid> wrote:
>> On 02/10/2021 01:05, Brian Gregory wrote:
>> >
>> > Anyone know what gets used for fire suppression nowadays?
>
>> I should know this, because I worked for a fire extinguisher servicing
>> firm for a year, but it was long time ago ...
>
>> General purpose extinguishers contain a mixture of water and another
>> substance such that, when the pressure is released, a fire retardant
>> foam is ejected, and are red in colour.
>
>> Anything electrical on fire, use CO2 extinguishers, which are black.
>
>
>All fire extinguishers are RED - an EU requirement. And, yes, I remeber
>black co2 ones.

and brass ones WWII
--

Martin in Zuid Holland

On 02/10/2021 12:05, Tweed wrote:
> SH <i.love.spam@spam.com> wrote:
>> On 02/10/2021 11:45, Tweed wrote:
>>> Adrian Caspersz <email@here.invalid> wrote:
>>>> On 02/10/2021 01:05, Brian Gregory wrote:
>>>>> On 01/10/2021 08:40, SH wrote:
>>>>>> Halons are also known as CFC's Chloro - Fluoro carbons.
>>>>>>
>>>>>> They were heavily used in refrigeration, air conditioning, fire
>>>>>> suppression systems and as an aerosol can propellant.
>>>>>>
>>>>>> It used to even be used in Tippex and Snopake until the water based
>>>>>> versions versions came along.
>>>>>>
>>>>>> Now its R134a  which has now been replaced with R1234yf
>>>>>>
>>>>>> https://www.climalife.co.uk/r134a
>>>>>>
>>>>>>
>>>>>> https://www.climalife.co.uk/r1234yf
>>>>>
>>>>> Those pages discuss r134a and r1234yf being used for refrigeration.
>>>>> The penultimate paragraph on the latter page says "R1234yf has an ASHRAE
>>>>> class A2L which means it’s mildly flammable." so I doubt it's used for
>>>>> fire suppression.
>>>>>
>>>>> Anyone know what gets used for fire suppression nowadays?
>>>>>
>>>>
>>>> I don't know how popular it is now (been 12 yrs), but there is a
>>>> replacement gas called Inergen,
>>>>
>>>> http://www.tyco.no/products/Gaseous-Fire-Suppression/inergen-overview
>>>>
>>>> which when deployed reduces oxygen content of the room mix and also
>>>> calms down humans so that they reduce anxiety breathing rate.
>>>>
>>>> Inergen gas dump
>>>> https://www.youtube.com/watch?v=0F7qyY15_14
>>>>
>>>> Nice demo. Participants so willing!
>>>>
>>>
>>> Genuine question - why can’t you use nitrogen to suppress fire in a data
>>> centre?
>>>
>>
>> The atmosphere comprises of 78% nitrogen already. The level of Oxygen is
>> about 21% with about 1% Argon.
>>
>> Remember the triangle of fire.... Oxygen - heat - fuel.
>>
>> You need to remove of these to extinguish the fire effectively.
>>
>> It is the 78% nitrogen in the atmosphere that leads to the formation of
>> nitrogen oxides from vehicle engines, the NOX would fall if we supplied
>> pure oxygen from cylinders rather than the ambient atmosphere
>>
>> So in a fire, you'd be making NOx due to the atmosphere containing both
>> nitrogen and oxygen,
>>
>> So you need a way of scavenging the oxygen quickly to quench a fire.
>> Thats why Halons were preferred as they do react with both oxygen and ozone.
>>
>> Another method is to use a gas or solid that decomposes when in contact
>> with a flame to retard the fire. This is the prupose of antimony
>> trioxide when added to flammable plastics to impart fire retardancy.
>>
>> S.
>>
>>
> Thank you, but I’m not sure I fully understand. If you vent a large volume
> of nitrogen into the room isn’t it going to displace the oxygen?
>

Wow....

Nitrogen based fire suppression systems do exist!

https://www.kidde-fenwal.com/Public/System_Details/Kidde-Fire-Systems/Nitrogen-Suppression-System

SH <i.love.spam@spam.com> wrote:
> On 02/10/2021 12:05, Tweed wrote:
>> SH <i.love.spam@spam.com> wrote:
>>> On 02/10/2021 11:45, Tweed wrote:
>>>> Adrian Caspersz <email@here.invalid> wrote:
>>>>> On 02/10/2021 01:05, Brian Gregory wrote:
>>>>>> On 01/10/2021 08:40, SH wrote:
>>>>>>> Halons are also known as CFC's Chloro - Fluoro carbons.
>>>>>>>
>>>>>>> They were heavily used in refrigeration, air conditioning, fire
>>>>>>> suppression systems and as an aerosol can propellant.
>>>>>>>
>>>>>>> It used to even be used in Tippex and Snopake until the water based
>>>>>>> versions versions came along.
>>>>>>>
>>>>>>> Now its R134a  which has now been replaced with R1234yf
>>>>>>>
>>>>>>> https://www.climalife.co.uk/r134a
>>>>>>>
>>>>>>>
>>>>>>> https://www.climalife.co.uk/r1234yf
>>>>>>
>>>>>> Those pages discuss r134a and r1234yf being used for refrigeration.
>>>>>> The penultimate paragraph on the latter page says "R1234yf has an ASHRAE
>>>>>> class A2L which means it’s mildly flammable." so I doubt it's used for
>>>>>> fire suppression.
>>>>>>
>>>>>> Anyone know what gets used for fire suppression nowadays?
>>>>>>
>>>>>
>>>>> I don't know how popular it is now (been 12 yrs), but there is a
>>>>> replacement gas called Inergen,
>>>>>
>>>>> http://www.tyco.no/products/Gaseous-Fire-Suppression/inergen-overview
>>>>>
>>>>> which when deployed reduces oxygen content of the room mix and also
>>>>> calms down humans so that they reduce anxiety breathing rate.
>>>>>
>>>>> Inergen gas dump
>>>>> https://www.youtube.com/watch?v=0F7qyY15_14
>>>>>
>>>>> Nice demo. Participants so willing!
>>>>>
>>>>
>>>> Genuine question - why can’t you use nitrogen to suppress fire in a data
>>>> centre?
>>>>
>>>
>>> The atmosphere comprises of 78% nitrogen already. The level of Oxygen is
>>> about 21% with about 1% Argon.
>>>
>>> Remember the triangle of fire.... Oxygen - heat - fuel.
>>>
>>> You need to remove of these to extinguish the fire effectively.
>>>
>>> It is the 78% nitrogen in the atmosphere that leads to the formation of
>>> nitrogen oxides from vehicle engines, the NOX would fall if we supplied
>>> pure oxygen from cylinders rather than the ambient atmosphere
>>>
>>> So in a fire, you'd be making NOx due to the atmosphere containing both
>>> nitrogen and oxygen,
>>>
>>> So you need a way of scavenging the oxygen quickly to quench a fire.
>>> Thats why Halons were preferred as they do react with both oxygen and ozone.
>>>
>>> Another method is to use a gas or solid that decomposes when in contact
>>> with a flame to retard the fire. This is the prupose of antimony
>>> trioxide when added to flammable plastics to impart fire retardancy.
>>>
>>> S.
>>>
>>>
>> Thank you, but I’m not sure I fully understand. If you vent a large volume
>> of nitrogen into the room isn’t it going to displace the oxygen?
>>
>
>
> Wow....
>
> Nitrogen based fire suppression systems do exist!
>
> https://www.kidde-fenwal.com/Public/System_Details/Kidde-Fire-Systems/Nitrogen-Suppression-System
>
I knew I was a genius :) (not to be taken seriously….)

On 02/10/2021 11:54, SH wrote:
> On 02/10/2021 11:45, Tweed wrote:

>> Genuine question - why can’t you use nitrogen to suppress fire in a data
>> centre?
>
> The atmosphere comprises of 78% nitrogen already. The level of Oxygen is
> about 21% with about 1% Argon.
>
> Remember the triangle of fire.... Oxygen - heat - fuel.
>
> You need to remove of these to extinguish the fire effectively.
>
> It is the 78% nitrogen in the atmosphere that leads to the formation of
> nitrogen oxides from vehicle engines, the NOX would fall if we supplied
> pure oxygen from cylinders rather than the ambient atmosphere
>
> So in a fire, you'd be making NOx due to the atmosphere containing both
> nitrogen and oxygen,

Not to any significant extent. Anyway, the immediate concern is putting
the fire out, not worrying what Greta might say.

> So you need a way of scavenging the oxygen quickly to quench a fire.
> Thats why Halons were preferred as they do react with both oxygen and
> ozone.

They're actually very inert and don't react in the way you say at all
easily.

Their stability and lack of reactivity are in fact what causes
atmospheric problems.

Halons and carbon dioxide are actually used in preference to nitrogen
because they are denser than air and hence form a carpet of non oxygen
containing gas around the base of the fire so it is starved of oxygen
that way.

Nitrogen could be used if it can be pumped in sufficient volumes to push
out all the oxygen, but it's obviously the same density as air and is a
bit flighty so doesn't hang around in the same way. It would require a
large installation too. Ordinary portable fire extinguishers containing
nitrogen would be pretty useless.

On 02/10/2021 12:42, Tweed wrote:
> SH <i.love.spam@spam.com> wrote:
>> On 02/10/2021 12:05, Tweed wrote:
>>> SH <i.love.spam@spam.com> wrote:
>>>> On 02/10/2021 11:45, Tweed wrote:
>>>>> Adrian Caspersz <email@here.invalid> wrote:
>>>>>> On 02/10/2021 01:05, Brian Gregory wrote:
>>>>>>> On 01/10/2021 08:40, SH wrote:
>>>>>>>> Halons are also known as CFC's Chloro - Fluoro carbons.
>>>>>>>>
>>>>>>>> They were heavily used in refrigeration, air conditioning, fire
>>>>>>>> suppression systems and as an aerosol can propellant.
>>>>>>>>
>>>>>>>> It used to even be used in Tippex and Snopake until the water based
>>>>>>>> versions versions came along.
>>>>>>>>
>>>>>>>> Now its R134a  which has now been replaced with R1234yf
>>>>>>>>
>>>>>>>> https://www.climalife.co.uk/r134a
>>>>>>>>
>>>>>>>>
>>>>>>>> https://www.climalife.co.uk/r1234yf
>>>>>>>
>>>>>>> Those pages discuss r134a and r1234yf being used for refrigeration.
>>>>>>> The penultimate paragraph on the latter page says "R1234yf has an ASHRAE
>>>>>>> class A2L which means it’s mildly flammable." so I doubt it's used for
>>>>>>> fire suppression.
>>>>>>>
>>>>>>> Anyone know what gets used for fire suppression nowadays?
>>>>>>>
>>>>>>
>>>>>> I don't know how popular it is now (been 12 yrs), but there is a
>>>>>> replacement gas called Inergen,
>>>>>>
>>>>>> http://www.tyco.no/products/Gaseous-Fire-Suppression/inergen-overview
>>>>>>
>>>>>> which when deployed reduces oxygen content of the room mix and also
>>>>>> calms down humans so that they reduce anxiety breathing rate.
>>>>>>
>>>>>> Inergen gas dump
>>>>>> https://www.youtube.com/watch?v=0F7qyY15_14
>>>>>>
>>>>>> Nice demo. Participants so willing!
>>>>>>
>>>>>
>>>>> Genuine question - why can’t you use nitrogen to suppress fire in a data
>>>>> centre?
>>>>>
>>>>
>>>> The atmosphere comprises of 78% nitrogen already. The level of Oxygen is
>>>> about 21% with about 1% Argon.
>>>>
>>>> Remember the triangle of fire.... Oxygen - heat - fuel.
>>>>
>>>> You need to remove of these to extinguish the fire effectively.
>>>>
>>>> It is the 78% nitrogen in the atmosphere that leads to the formation of
>>>> nitrogen oxides from vehicle engines, the NOX would fall if we supplied
>>>> pure oxygen from cylinders rather than the ambient atmosphere
>>>>
>>>> So in a fire, you'd be making NOx due to the atmosphere containing both
>>>> nitrogen and oxygen,
>>>>
>>>> So you need a way of scavenging the oxygen quickly to quench a fire.
>>>> Thats why Halons were preferred as they do react with both oxygen and ozone.
>>>>
>>>> Another method is to use a gas or solid that decomposes when in contact
>>>> with a flame to retard the fire. This is the prupose of antimony
>>>> trioxide when added to flammable plastics to impart fire retardancy.
>>>>
>>>> S.
>>>>
>>>>
>>> Thank you, but I’m not sure I fully understand. If you vent a large volume
>>> of nitrogen into the room isn’t it going to displace the oxygen?
>>>
>>
>>
>> Wow....
>>
>> Nitrogen based fire suppression systems do exist!
>>
>> https://www.kidde-fenwal.com/Public/System_Details/Kidde-Fire-Systems/Nitrogen-Suppression-System
>>
> I knew I was a genius :) (not to be taken seriously….)
>

To be fair, you would *not* want to be in the room when or you would be
asphyxiated to death.....

In article <8gfglgt1d3c7uer89o6ndr6i8gv3auhcod@4ax.com>,
Martin <me@address.invalid> wrote:
> On Sat, 02 Oct 2021 08:44:29 +0100, charles <charles@candehope.me.uk> wrote:

> >In article <sj89rf$hkk$1@gioia.aioe.org>,
> > Java Jive <java@evij.com.invalid> wrote:
> >> On 02/10/2021 01:05, Brian Gregory wrote:
> >> >
> >> > Anyone know what gets used for fire suppression nowadays?
> >
> >> I should know this, because I worked for a fire extinguisher servicing
> >> firm for a year, but it was long time ago ...
> >
> >> General purpose extinguishers contain a mixture of water and another
> >> substance such that, when the pressure is released, a fire retardant
> >> foam is ejected, and are red in colour.
> >
> >> Anything electrical on fire, use CO2 extinguishers, which are black.
> >
> >
> >All fire extinguishers are RED - an EU requirement. And, yes, I remeber
> >black co2 ones.

> and brass ones WWII

I can remember a brass one in parent's car.

--
from KT24 in Surrey, England
"I'd rather die of exhaustion than die of boredom" Thomas Carlyle

On 02/10/2021 11:10, Java Jive wrote:

>> One website for room fire suppression at
>> <https://www.safelincs.co.uk/redetec-novec1230-automatic-fire-suppression-unit/?q=Novec+1230>
>> turns up with "Novel 1230" as the fire suppressant. I had to go to the
>> MSDS to see what that was, and it is listed as:
>> 1, 1, 1, 2, 2, 4, 5, 5, 5 – Nonafluoro-4-(Trifluoromethyl)-3-Pentanone
>> (misspelt in both the MSDS and Data Sheet in different ways!).
>>
>> There's another halocarbon mentioned elsewhere (HCFC-123, R-123 -
>> 1,1-Dichloro-2,2,2,-Trifluoroethane), and I suspect there are others.
>
> I presume that these are variants that don't harm the ozone layer that
> have been developed since. I remember my then boss being concerned at
> the time about the implications for his business.

HCFC-123 is said to have an ODF (Ozone Depletion Potential) of 0.012.
This is pretty low according to
<https://en.wikipedia.org/wiki/Ozone_depletion_potential>.
More info and links at
<https://en.wikipedia.org/wiki/2,2-Dichloro-1,1,1-trifluoroethane>
But it also has a Global Warming Potential similar to methane (around 75).

Novec-1230 (*not* Novel-1230! That'll teach me for pointing out
misspellings) is much better. According to 3M, it has zero ODF and a GWP
of <1.
<https://www.3m.co.uk/3M/en_GB/novec-uk/applications/fire-suppression/>

--

Jeff

On 02/10/2021 11:45, Tweed wrote:
> Genuine question - why can’t you use nitrogen to suppress fire in a data
> centre?
>

Apparently Inergen is just a mixture of 52% Nitrogen, 40% Argon and 8% CO2.

--
Brian Gregory (in England).

On 02/10/2021 12:05, Tweed wrote:
> Thank you, but I’m not sure I fully understand. If you vent a large volume
> of nitrogen into the room isn’t it going to displace the oxygen?

I imagine the problem is the large volume. Nitrogen needs serious
cryogenics to store it in liquid form which would probably be necessary
to store it adequately compactly. You'd probably also need a lot of
heat input to the storage system to evaporate it quickly.

I imagine that's why CO2 is preferred for stunning animals in
slaughterhouses, with the added complication that you need to get it
fully to room temperature and humidify it.

On 29/09/2021 17:37, NY wrote:
> Quite apart from the fact that the (Halon?) gas would suffocate you in
> the same way that it's intended to "suffocate" a fire, wouldn't want to
> be close to the gas discharge

Halogen systems are designed to suppress free radicals in fires, and
therefore quench the chemical reactions, rather more than just replace
the air.

Their risk to humans, as well as suffocation, is that they tend to be
anaesthetics.

On Sat, 02 Oct 2021 14:18:19 +0100, charles <charles@candehope.me.uk> wrote:

>In article <8gfglgt1d3c7uer89o6ndr6i8gv3auhcod@4ax.com>,
> Martin <me@address.invalid> wrote:
>> On Sat, 02 Oct 2021 08:44:29 +0100, charles <charles@candehope.me.uk> wrote:
>
>> >In article <sj89rf$hkk$1@gioia.aioe.org>,
>> > Java Jive <java@evij.com.invalid> wrote:
>> >> On 02/10/2021 01:05, Brian Gregory wrote:
>> >> >
>> >> > Anyone know what gets used for fire suppression nowadays?
>> >
>> >> I should know this, because I worked for a fire extinguisher servicing
>> >> firm for a year, but it was long time ago ...
>> >
>> >> General purpose extinguishers contain a mixture of water and another
>> >> substance such that, when the pressure is released, a fire retardant
>> >> foam is ejected, and are red in colour.
>> >
>> >> Anything electrical on fire, use CO2 extinguishers, which are black.
>> >
>> >
>> >All fire extinguishers are RED - an EU requirement. And, yes, I remeber
>> >black co2 ones.
>
>> and brass ones WWII
>
>I can remember a brass one in parent's car.

I can remember the evacuees stealing them from road side Nissen huts that were
full of military stuff in 1944.
--

Martin in Zuid Holland

SH wrote:

> The atmosphere comprises of 78% nitrogen already. The level of Oxygen is about
> 21% with about 1% Argon.
>
> Remember the triangle of fire.... Oxygen - heat - fuel.
>
> You need to remove of these to extinguish the fire effectively.

All the server rooms I work in use FM200 (heptafluoropropane) fire suppression
which works by removing the heat part of the fire triangle, not the oxygen.

Andy Burns <usenet@andyburns.uk> wrote:
> SH wrote:
>
>> The atmosphere comprises of 78% nitrogen already. The level of Oxygen is about
>> 21% with about 1% Argon.
>>
>> Remember the triangle of fire.... Oxygen - heat - fuel.
>>
>> You need to remove of these to extinguish the fire effectively.
>
> All the server rooms I work in use FM200 (heptafluoropropane) fire suppression
> which works by removing the heat part of the fire triangle, not the oxygen.
>

Does the system also trash your server disks?

Tweed wrote:

> Andy Burns <usenet@andyburns.uk> wrote:
>
>> SH wrote:
>>
>>> Remember the triangle of fire.... Oxygen - heat - fuel.
>>> You need to remove of these to extinguish the fire effectively.
>>
>> All the server rooms I work in use FM200 (heptafluoropropane) fire suppression
>> which works by removing the heat part of the fire triangle, not the oxygen.
>
> Does the system also trash your server disks?

I've never heard of one actually going off, let alone experienced it, there are
"delay" buttons you can press to allow an extra few seconds to get out. The
pipework and nozzles are quite chunky (about 2" with nozzles every couple of
meters, each having several 10mm holes) I wouldn't have expected it to be so
powerful as to wreck drives.

Andy Burns wrote:

> Tweed wrote:
>
>> Andy Burns <usenet@andyburns.uk> wrote:
>>
>>> All the server rooms I work in use FM200 (heptafluoropropane) fire suppression
>>> which works by removing the heat part of the fire triangle, not the oxygen.
>>
>> Does the system also trash your server disks?
>
> I wouldn't have expected it to be so
> powerful as to wreck drives.

The system suppliers seem keen to differentiate the inert/clean gas systems from
the fm200 systems, saying there are known cases of damage from the former, but
not from the latter ... but reddit says otherwise.

On Sat, 2 Oct 2021 13:56:00 +0100, SH <i.love.spam@spam.com> wrote:

> To be fair, you would *not* want to be in the room when or you would be
> asphyxiated to death.....

Is there any other outcome of asphyxiation?

Can you be electrocuted and survive?

Some people do write rubbish.

Paul Ratcliffe <abuse@orac12.clara34.co56.uk78> wrote:
> On Sat, 2 Oct 2021 13:56:00 +0100, SH <i.love.spam@spam.com> wrote:
>
>> To be fair, you would *not* want to be in the room when or you would be
>> asphyxiated to death.....
>
> Is there any other outcome of asphyxiation?

Yes, if help gets to you in time.

Definition: deprivation of oxygen that can result in unconsciousness and
often death

>
> Can you be electrocuted and survive?

Yes.
Definition: : to kill or severely injure by electric shock
>
> Some people do write rubbish.
>
They do indeed.

On Tue, 5 Oct 2021 06:36:54 -0000 (UTC), Tweed
<usenet.tweed@gmail.com> wrote:

>> Can you be electrocuted and survive?
>
>Yes.
>Definition: : to kill or severely injure by electric shock
>>
>> Some people do write rubbish.
>>
>They do indeed.

Curious. My edition of the OED (on CDROM V2) puts it like this-

[begin quote]
1. Put to death by a strong electric current as a means of capital
punishment. L19.

2. Cause death of by electric shock. E20.

• electro"cution noun execution by electricity; death caused by
electricity: L19.
[end quote]

If yours is more recent, they must have downgraded it. I suppose the
OED has abolished the death penalty.

Rod.

On 05/10/2021 09:46, Roderick Stewart wrote:
> On Tue, 5 Oct 2021 06:36:54 -0000 (UTC), Tweed
> <usenet.tweed@gmail.com> wrote:
>
>>> Can you be electrocuted and survive?
>>
>> Yes.
>> Definition: : to kill or severely injure by electric shock
>>>
>>> Some people do write rubbish.
>>>
>> They do indeed.
>
> Curious. My edition of the OED (on CDROM V2) puts it like this-
>
> [begin quote]
> 1. Put to death by a strong electric current as a means of capital
> punishment. L19.
>
> 2. Cause death of by electric shock. E20.
>
> • electro"cution noun execution by electricity; death caused by
> electricity: L19.
> [end quote]
>
> If yours is more recent, they must have downgraded it. I suppose the
> OED has abolished the death penalty.

I think that it's just another of those words which has changed in
meaning over the years. I see that its derivation is "electro" and
"execution". I can't see any doubt over what that entails. But note that
the original meaning was an active form - to put to death by electricity.

However, many definitions seem now to include severe injury, and I think
that's because the original usage is rare, even in the USA. It also
became associated with /passive/ shock, rather than active shock (the
latter having to result in death as sentenced by the court), and passive
shock might be survivable.

--

Jeff

On 05/10/2021 09:46, Roderick Stewart wrote:
> On Tue, 5 Oct 2021 06:36:54 -0000 (UTC), Tweed
> <usenet.tweed@gmail.com> wrote:
>
>>> Can you be electrocuted and survive?
>>
>> Yes.
>> Definition: : to kill or severely injure by electric shock
>>>
>>> Some people do write rubbish.
>>>
>> They do indeed.
>
> Curious. My edition of the OED (on CDROM V2) puts it like this-
>
> [begin quote]
> 1. Put to death by a strong electric current as a means of capital
> punishment. L19.
>
> 2. Cause death of by electric shock. E20.
>
> • electro"cution noun execution by electricity; death caused by
> electricity: L19.
> [end quote]
>
> If yours is more recent, they must have downgraded it. I suppose the
> OED has abolished the death penalty.
>

"The Oxford English Dictionary is not an arbiter of proper usage,
despite its widespread reputation to the contrary. The Dictionary is
intended to be descriptive, not prescriptive. In other words, its
content should be viewed as an objective reflection of English language
usage, not a subjective collection of usage ‘dos’ and ‘don'ts’."

--
Robin
reply-to address is (intended to be) valid